1. Field
The present invention relates to thin-film transistors (TFTs), and more particularly, to a TFT sensor having an oxide semiconductor layer as an active layer.
2. Description of the Related Art
Performance of a thin-film transistor (TFT) greatly depends on the material and state of an active layer in which a channel, through which charge carriers move, is formed.
In the case of TFTs having an active layer formed of amorphous silicon (hereinafter, referred to as an amorphous silicon TFT), charge mobility is very low, namely, about 0.5 cm2/Vs.
In the case of TFTs having an active layer formed of polycrystalline silicon (hereinafter, referred to as polycrystalline silicon TFTs), a crystallization process, an impurity-implantation process, an activation process, etc. are required, and thus a manufacturing process thereof is complicated and a manufacturing cost thereof is high, compared to amorphous silicon TFTs.